Equipments when subjected to cyclic loads may fail due to fatigue. As an illustration consider an example of a wire being bent back and forth until the plastic deformations grow so that it ruptures. In ASME fatigue analysis typically the cyclic loads are pressure and/or temperature. Here an ASME PTB-3 Validation for “Example E5.5.3 – Elastic Stress Read more about ASME PTB-3 Validation – Fatigue Analysis[…]

Linear/Eigenvalue Buckling analysis are fairly easy to set up and post process. Typically an Eigenvalue Buckling Analysis is preceded by a static structural analysis with perturbation load leading to compressive stress field being generated in the model. The pre-stressed model from the static structural analysis is then analyzed for buckling failure modes. Results of buckling Read more about ASME PTB-3 Validation – Buckling Analysis[…]

In addition to demonstrating protection against plastic collapse, the analyzed components must also qualify the local failure check per section 5.3 of ASME Sec VIII Div 2. The code gives two analysis methodologies to do this.The first method is to carry out an elastic analysis and check triaxial stress limit given as 4S by eq Read more about ASME PTB-3 Validation – Protection Against Local Failure[…]

Elastic Plastic Analysis is a non-linear analysis. There are two main non-linearities involved here. The material model is non-linear and requires true stress strain curve as input. In contrast a linear static analysis just needs Elastic Young’s Modulus to construct the full stress strain curve. The stress-strain curve in this case is simply a line Read more about ASME PTB-3 Validation – Elastic Plastic Analysis[…]

Limit Load analysis are non linear in nature and may require significantly more computation time and resource than a linear elastic analysis. As such a linear elastic analysis is always a recommended first step. It helps to ensure the FEA problem is correctly setup i.e. there are no rigid body motions, deformations and far field Read more about ASME PTB-3 Validation – Limit Load Analysis[…]

While solid elements are robust for local stress computations and require much less care in analysis setup, the problem size (number of elements and nodes) blows up pretty quickly if the extent of modelling is increased (Say modelling a local shell to nozzle region vs modelling entire shell with nozzle). This is where shell elements Read more about Shell Elements for Pressure Vessel Design[…]

For ASME UHX heat exchangers, the design and analysis of thick flanged and flued expansion joints need to be carried out using FEA. Though the user can take various different approaches to achieve this, the analysis methodology recommended by TEMA (RCB-8) has become sort of standard in the industry. TEMA analysis guidelines are very well Read more about Flanged and Flued Expansion Joint[…]

I saw that curtain rods at my house were bent due to the weight of curtains on them and wondered whether a beam analysis can be carried out to verify its deformation under the load. Here is a picture of the initially straight curtain rod without curtains. And here is a picture of the bent Read more about Curtain Rod – A Simply Supported Beam[…]